Springy support for upholstery



5 Sheets-Sheet 1 Filed July 18, 1963 March 23, 1965 K. WOLFF 3,174,741

SPRINGY SUPPORT FOR UPHOLSTERY Filed July 18, 1963 5 Sheets-Sheet 2 March 23, 1965 K. WOLFF 3,174,741

SPRINGY SUPPORT FOR UPI-IOLSTERY Filed July 18, 1963 5 Sheets-Sheet :s

F/Ga" F764 //v VN TOR k/i PL 4 44 FF March 23, 1965 K. WOLFF SPRINGY SUPPORT FOR UPHOLSTERY 5 Sheets-Sheet 4 Filed July 18, 1963 lNVE/VTOR A m 4/04 FF March 23, 1965 WQLFF 3,174,741

SPRINGY SUPPORT FOR UPHOLSTERY Filed July 18, 1963 5 Sheets-Sheet 5 United States Patent Oflice 3,174,741 Patented Mar. 23, 1965 3,174,741 SPRING?! SUPPQRT FOR UPHOLSTERY Karl Wolff, Ennepetai-hlilspe, Westphalia, Germany,

assignor to Garthe-Wolif K.G., Ennepetai-Milspe, Westphalia, Germany Filed July 18, 1963, Ser. No. 2%,060 Claims priority, application Germany, July 20, 1962,

G 263%; Oct. 27, 1962, G 36,250

19 Claims. t Cl. 267-110) This invention relates to sprin-gy supports, and more specifically to a springy support for upholstery comprising a plurality of spring bows arranged side by side and secured to a frame or the like.

it is the object of the invention to improve such springy supports for upholstery and particularly to prolong their service life.

This object is achieved according to the invention by providing a springy support for upholstery which comprises a base and a plurality of one-piece spring bows arranged side by side and secured to said base, said spring bows consisting of an elastically resilient, noncorrosive synthetic plastics material selected from the group consisting of acetal resins, and having a flat reinforced cross section.

This provides in a simple manner a springy support for upholstery which has a great durability and is easy to manufacture in an inexpensive manner. By varying the number of the spring bows arranged side by side the size of the springy support for upholstery can be changed as desired.

Preferably the spring bows have a substantially rectangular cross-sectional area and are provided on their rear side with a longitudinally extending central reinforcing rib. Due to this the spring bows have a large area smooth outer surface, the reinforcing ribs being directed inwardly. Furthenmore, the elasticity of the spring bows over their entire length or over part thereof can be adapted to the actual requirements by increasing or reducing the reinforcing rib in size.

Expediently, the spring bows arranged side by side at a distance apart have cross connections arranged at least at their ends or, if desired, distributed over their lengths. These cross connections may be in the form of plug and socket-type connections, one longitudinal side of the spring bows having plug-type projections associated therewith and the other longitudinal side having socket-type receptions associated therewith. This substantially simplifies the manufacture of the springy support for upholstery since first the spring bows can be fitted together to form a springy support of any desired width which can then be secured to a frame as a whole.

In a particularly expedient manner the ends of the spring bows may have transverse webs on their one side and projections on their other side, which parts can be positively connected together. The transverse webs may be provided on their rear side with grooves of dove-- tailed cross section which extend into the free end face of the transverse webs and have widened portions at their ends remote from the free end faces, whereas the projections have a cross-sectional area corresponding to the dovetailed cross section of the groove and carry at their free ends heads corresponding to the widened por- L ons of the grooves. This enables the projections of the spring bows to be inserted into the grooves of other spring bows, the heads being engageable in the widened portions of the grooves. When inserting the projections into the grooves, a portion of the projections the crosssectional area of which corresponds to the dovetailed cross section of the groove snaps into the groove. This snapping action is possible because the transverse webs as well as the spring bows are made of an elastic synthetic resin such as acetal resin. In some cases the cross connections between adjacent spring bows may consist of one piece with the latter.

The elastic deformability of the transverse webs may still be increased by providing the transverse webs on their front side with a. longitudinally extending groove like recess located above the groove of dovetailed cross section.

Advantageously, the spring bows may be secured to a wooden plate or a frame by screws passing through the transverse webs.

Several preferred embodiments of the invention will now be described by way of example and with reference to the accompanying dnawings, in which:

FIG. 1 is a fragmentary elevational View of a springy support for upholstery according to the invention which is formed of a plurality of parallel spring bows;

FIG. 2 is a section taken on the line IIII of FIG. 1;

FIG. 3 is a fragmentary elevational view, on an enlarged scale, showing the attachment of the spring bows;

FIG. 4 is a section taken on the line IVIV of FIG. 3;

PEG. 5 is a fragmentary elevational view, on an enlarged scale, showing the connection of the spring bows between each other;

FIG. 6 is a section taken on the line VIVI of FIG. 5;

FIG. 7 is a section taken on the line VHVII of FIG. 5;

FIG. 8 is a fragmentary elevational view of a springy support for upholstery made in one piece;

FIG. 9 is a section taken on the line IXiX of FIG. 8;

FIG. 10 is a fragmentary elevational view of a further embodiment of the springy support for upholstery;

FIG. 11 is a section taken on the line Xi-Xl of FIG. 10, and

FIG. 12 is a section taken on the line XII-XII of PEG. 10.

FIGS. 1 to 7 show a springy support 2G for upholstery which has a plurality of parallel spring bows 21 secured to a frame 23 by means of clamps 22. The frame 23 which is of tubular construction and may be made of metal and preferably of light metal or also of synthetic plastics materials, is formed of a U-shaped upper beam 24 and a likewise U-shaped lower beam 25, the free ends of the legs 26 of the upper beam 24 of the frame and the free ends of the legs 27 of the lower beam 25 of the frame being welded together. The frame 23 thus has a substantially rectangular form with the two upper corners rounded olf. As can be seen particularly from H6. 2, the vertex portion of the lower beam 25 of the frame is disposed behind the legs 26 of the upper beam of the frame and a transom 28 is arranged for reinforcing purposes below each leg 26 of the upper beam 24-.

The parallel spring bows 21 which are made of acetal resin are held by their clamps 22 on the vertex portions of the beams 24 md 25 of the frame 23. The clamps 22. are, as shown particularly in FIG. 4, constructed as hollow cylinders 2% provided with an axially extending slot 3t) and encompassing the tubular beams 2 and 25 of the frame 23. The length of the hollow cylinders 29 corresponds to the width of the spring bows 21. The width of the axial slot 36' amounts to a quarter of the cylinder circumference so that the slotted hollow cylinder 29 can he slipped on to the tubular beams 24 and 25, during which action the ends of the hollow cylinder 29 formed by the axial slot 39 are elastically forced apart. The axial slot 39 is arranged at the end opposite the spring how 21.

On its inner surface the hollow cylinder 29 has a central pin 31 which is opposite to the axial slot 3'2 and engages in a bore 32 in the tubular beams 24 and 25 of the frame 23. This prevents the clamps 22; from turning and laterally shifting on the tubular beams 24 and 25.

As can be seen particularly from FIG. 2, the spring bows 21 are curved and have a substantially rectangular cross-sectional area, a central reinforcing rib 33 extending on the rear of the spring bows 21 in the longitudinal direction thereof. The non-rotatable mounting of the clamps 22 provided at the ends of the spring bows 21 on the beams 24 and 25 of the frame 23 ensures that a compressive load acting on the spring bows 21 will merely cause an elastic deformation of the latter. As shown particularly in FIGS. 1 and to 7, the spring bows 21 of the springy support 20 are interconnected at several points. To this end, projections 34 having rectangular cross-sectional areas are provided on one side of the spring bows 21, while sockets 35 are disposed on the other side thereof. Thus the spring bows 21 are of uniform shape and can be made in one piece. When assembling the spring bows 21 to form the springy support 20, the projections 34 will have to be inserted into receptions 36 of the sockets 35. The outer surfaces of the projections 34 and the sockets 35 are located exactly in the same plane with the outer surfaces of the spring bows 21 so that a stepless transition of the outer surfaces is ensured. To provide space for the pocket-like receptions 36, the sockets 35 are thicker than the spring bows 21, the over-all height surmounting the thickness of the spring bows 21 being arranged within the arches of the spring bows 21. Since the sockets 35 together with their receptions 36 serve to accommodate the cooperating projections 34, they are of course wider than the projections 34. I

The receptions 36 are blind holes having a shape conforming to the contours of the projections 34. The projections 34 have a unilaterally offset portion and a shoulder 37 which, when the spring bows 21 are fitted together, abuts against the free end face of the sockets 35. The length of the ofiset portion of the projection 34 is somewhat shorter than the depth of the receptions 36. The shoulder 37 of the projections 34 is located on the side of the outer surface of the spring bows 21 to provide astepless transition from one spring bow 21 to the other and particularly from the projections 34 to the sockets 35. For this reason the width of the shoulder 37 corresponds to the wall thickness of the sockets 35.

As can be seen particlularly from FIG. 2, spring extensions 38 are formed on the spring bows 21 and extend tangentially upwards from the curves of the spring bows 21 so as to terminate a relatively short distance below the level of the clamps 22 attached to the upper beam 24 of the frame 23. The spring extensions 38 have a cross-sectional area which is equal to that of the spring bows 21. The free ends of the spring extensions 38 are interconnected and to this end, the ends are provided with rearwardly projecting thickened portions 39 in which the receptions 36 for the projections 34 areprovided. These projections 34 likewise have a shoulder 37 providing a stepless transition.

As already mentioned, the springy support 28 comprises a plurality of parallel spring bows 21. At the ends of the series of spring bows 21 the interconnected free ends of the spring extensions 38 are connected by means of corner springs 49 to the legs 26 of the upper beam 24 of the frame 23. Two different corner springs 44) are required for this purpose in the illustrated springy sup port 20, namely a right-handed and a left-handed corner spring. At their ends facing the spring extensions 38 the corner springs 40 have a reception 36 in which the projection 34 of the last spring extension 38 engages. Since, however, the spring bow 21 with its spring extension 38 arranged at one end of the series of spring bows 21 likewise has receptions 36 at its free side, the connection can be established with the aid of an intermediate piece 41 which can be placed into the receptions 36 facing each other. The end of the corner springs 49 facing the legs 26 of the upper beam 24 of the frame 23 is equipped with a clamp 22, as already described herein: before, and can be attached by means of this clamp to the tubular legs 26 of the upper beam 24 of the frame 23.

The connection of the parallel spring bows 21 to the legs 26 of the upper beam 24 of the frame 23 is effected by means of a terminal spring bow 42. The terminal spring bow 42 has the same curved shape as the spring bows 21. However, it is shorter than the spring bows 21 and has no clamps 22 at its ends for supporting it on the beams 24 and 25 of the frame 23. The terminal spring bows 42 are arranged parallel to the spring bows 21 and are each connected to the respective last one of the series of spring bows 21. To this end, the sockets 35 are provided on the side of the terminal spring bows 42 facing the spring bows 21 and have receptions 36 in which the projections 34 of the adjacent spring bow 21 engage. Since, however, as already mentioned, the spring bow 21 arranged at the one end of the series of spring bows 21 likewise has sockets 35 at its free side, the connection is effected also in this case by intermediate pieces 41. For connecting the terminal spring bow 42 to the legs 26 of the upper beam 24 of the frame 23 the terminal spring bow 42 is provided at its free side with a central supporting bow 43 which carries at its free end a clamp 22 by means of which the supporting bow 43 is attached to the tubular legs as of the beam 24 of the frame.

In the embodiment illustrated in FIGS. 8 and 9, the springy support 20 for upholstery is integral with a frame 44. The springy support 26 is made of acetal resin and has parallel spring bows 45 which are integrally formed with their ends on the frame 44 having a U-shaped crosssectional area and are integrally interconnected by means of a plurality of cross connections 46. As can be seen particularly from FIG. 9, the spring bows 45 have spring extensions 47 integrally formed thereon which extend in the same direction and tangentially to the curves of the spring bows 45 and terminate at the levels of the upper and lower legs of the frame 44, respectively. The ends of the spring extensions 47 are integrally interconnected by means of the cross connections 46. In a similar manner, corner springs 49 and terminal spring bows 50 are integrally connected to the spring bows 45 and the frame 44. The spring bows, the cross connections, the corner springs, the terminal spring bows and the spring extensions all have a similar rectangular cross-sectional area and on their rear sides a longitudinally extending reinforcing rib 48.

In the embodiment illustrated in FIGS. 10-12, spring bows 51 made of acetal resin have upper ends 52 bent rearwardly in a semicircle so that the upper ends 52 are located behind the arched portion of the spring bows 51. Thereby it is ensured that the springy support 20 is also elastic at these ends of the spring bows 51. The upper ends 52 and lower ends 53 of the spring bows 51 are interconnected through the intermediary of a wooden plate 55 or a frame and secured thereto by means of screws 54. As shown particularly in FIG. 10, transverse webs 56 are provided on the ends 52 and 53 of the spring bows 51 at one side thereof and have a length corresponding to the space left between the individual spring bows 51 of the springy support 20. The transverse webs 56 have grooves 57 in their rear sides which grooves 57 extend to the free end face of the transverse webs. These grooves 57 are of dovetailed cross section and have widened portions 58 at their ends remote from the free end face of the transverse Webs 56. Furthermore, the transverse webs 56 are provided on their front side with a longitudinally extending groove-like recess 59 which is located above the groove 57.

As can be seen from FIG 10, projections 60 are formed on the spring bows 51 at their side opposite to the transverse webs 56 and these projections have a cross-sectional area corresponding to the dovetailed cross section of the grooves 57 and carry at their free ends heads 61 corresponding to the widened portions 58 of the grooves 57. Thus, the projections 66 of the spring bows 51 are insertable into the grooves 57 of other spring bows 51, the heads 61 engaging in the widened portions 58 of the grooves 57. When inserting the projections 60 into the grooves 57, the portion of the projections 60 the crosssectional area of which corresponds to the dovetailed cross section of the groove 57 snaps into the groove 57. This snapping action is possible because the transverse webs 56 as weil as the spring bows 51 are made of an elastic acetal resin. The elastic deformability of the trans verse webs 56 is still increased by the groove-like recess 59 formed in the front face of the transverse webs. The spring bows 51 are thus positively connected with one another since they are also prevented from being pulled apart in the longitudinal direction of the groove 57 by the head 61 engaged in the widened portion 58 of the groove 57. The transverse webs 56 are provided with bores 62 through which the fixing screws 54 are passed. In the illustrated embodiment, the bores 62 are arranged in the region of the widened portion 58 and the head 61 engaged therein. It is self-evident that the bore 62 may also be arranged outside the region of the groove 57. The spring bows 51 are likewise fitted on the rear with a longitudinally extending central reinforcing rib 63 to increase the strength of the springy support.

As already mentioned, the invention is not limited to the illustrated embodiments but can be realized also in other forms of construction. For example, in the embodiment shown in FIGS. 1 to 7, spring extensions 38 may also be provided at the lower ends of the spring bows 21 and the spring bows be integrally interconnected. Furthermore, the spring bows 51 of the embodiment illustrated in FIGS. to 12 might be integrally interconnected by, and secured to, a frame or a plate in a different manner than that shown. The clamp 22, instead of engaging around the tubular beams of the frame in the fashion of a clamping collar, may also engage like a pair of pincers in grooves in the frame. Also, for connecting the individual spring bows, each spring bow may be provided with projections on both sides thereof so that the opposed projections of two spring bows are connectible by means of a loose sleeve.

I claim:

1. A springy support for upholstery comprising a base and a plurality of one-piece spring bows arranged side by side and secured to said base, said spring bows consisting of an elastically resilient, noncorrosive synthetic plastics material selected from the group consisting of acetal resins, and having a substantially rectangular cross section and a longitudinally extending reinforcing rib on the concave side thereof.

2. A springy support for upholstery comprising, in combination, a base; and a plurality of spring bows arranged side by side spaced from each other and secured at opposite ends thereof to said base, said spring bows consisting of elastically resilient, non-corrosive plastics material selected from the group consisting of acetal resins, and each having a substantially rectangular cross section and a longitudinally extending reinforcing rib at the concave side thereof, each of said spring bows being provided with attachment ends including a transverse web projecting to one side of each spring bow and having a female receiving end, and a projection projecting to the other side of the spring bow and having a free end received in said receiving end of the adjacent spring bow.

3. A springy support as claimed in claim 2, wherein grooves of dovetailed cross section are provided on the rear side of the transverse Webs and extend to the free end face of the transverse webs, widened portions adjoin said grooves at their ends remote from the free end faces, the projections have a cross-sectional area corresponding to the dovetailed cross section of the groove and heads are carried at the free ends of the projections, said heads corresponding to the widened portions of the grooves.

4. A springy support as claimed in claim 3, wherein a longitudinally extending groove-like recess is formed in the front face of each transverse web and located above the groove of dovetailed cross section.

5. A springy support for upholstery comprising, in combination, a base; a plurality of spring bows arranged side by side spaced from each other and secured at opposite ends to said base, said spring bows consisting of elastically resilient, non-corrosive plastics material selected from the group consisting of acetal resins and having each a substantially rectangular cross section and a longitudinally extending reinforcing rib at the concave side thereof; and cross connections distributed over the length of said bows intermediate their ends and including sockettype members associated with one longitudinal side of each bow and plug-type projections associated with the other side of each bow and respectively engaged in the socket-type members in the spring bow adjacent thereto.

6. A springy support as claimed in claim 5, wherein a unilaterally recessed portion is provided on each projection so that an offset edge is formed on said projection, which offset edge corresponds in width to the wall thickness of the socket and bears against the free end face of the socket.

7. A springy support as claimed in claim 2, wherein the cross connections and the spring bows are made in one piece.

8. A springy support as claimed in claim 7, wherein the cross connections have the same cross sectional area as the spring bows anda longitudinally extending reinforcing rib is provided on the rear side of each cross connection.

9. A springy support as set forth in claim 5, wherein said base comprises a tubular frame, and including clamps at the ends of said spring bows for detachably securing said spring bows to said tubular frame, each of said clamps consisting of a cylinder integral with the spring bow, engaged around the tubular frame and being axially slotted diametrically opposite the respective end of the spring how.

10. A springy support as claimed in claim 9, wherein the width of the axial slot amounts to a quarter of the circumference of the hollow cylinder.

l-l. A springy support as claimed in claim 9, wherein a central pin is provided on the inner surface of the cylinder and arranged opposite to the slot and a bore is formed in the tubular frame and engaged by said central pm.

12. A springy support as set forth in claim 5, wherein said base comprises a tubular frame including a U-shaped upper and a U-shaped lower beam each having legs, wherein a vertex portion of the lower beam is arranged behind the legs of said upper beam, and including a transom for reinforcing purpose below each leg of said upper beam.

13. A springy support for upholstery comprising, in combination, a base; a plurality of spring bows arranged side by side spaced from each other and secured at opposite ends thereof to said base, said spring bows consisting of elastically resilient, non-corrosive plastics material selected from the group consisting of acetal resins and having each a substantially rectangular cross section and a longitudinally extending reinforcing rib at the concave side thereof; at least one spring extension for each spring bow integrally connected at one end thereof to said bow at a portion of the latter intermediate the crest and one secured end thereof and projecting from said portion toward said secured end in a plane substantially parallel to said base; and means for connecting the free ends of adjacent spring extensions to each other.

14. A springy support as set forth in claim 13, wherein said means for connecting adjacent spring extensions comprise a thickened portion at the free end of each extension and formed with a cavity therein open to one side of said extension and a transverse projection projecting 7 to the other side of the extension and having a free end snugly received in the cavity of the adjacent extension.

15. A springy support as set forth in claim 13, wherein saidmeans for connecting adjacent spring extensions comprise a transverse web integrally connecting the ends of said spring extensions distant from the spring bows to each other.

16. A springy support as set forth in claim 13, wherein said base comprises a substantially rectangular frame and wherein said frame bows and spring extensions extend substantially parallel to the shorter sides of said frame, and including a corner spring connecting the free end of the spring extension adjacent the shorter side of the frame with the latter, said corner spring being connected at opposite ends to said spring extension and to said shorter side of said frame.

17. A springy support for upholstery comprising, in combination, a substantially rectangular frame; a plurality of spring bows arranged side by side spaced from each other in planes substantially parallel to the shorter sides of the frame and being respectively connected at opposite ends thereof to the longer sides of the latter, said spring bows consisting of elastically resilient, non-corrosive plastics material selected from the group consisting of acetal resins, and having each a substantially rectangular cross section and a longitudinally extending reinforcing rib at the concave side thereof; a plurality of cross connecting means extending spaced from each other transverse of said spring bows and connecting longitudinally spaced portions thereof to each other; a terminal spring bow arranged between each shorter side of said frame and a spring bow adjacent thereto and extending spaced from and substantially parallel to the latter, said terminal bow having opposite free ends; additional transverse connecting means connecting said terminal bows to the spring bows adjacent thereto; and a supporting bow integrally connected to a portion of each terminal bow intermediate the ends of the latter and at the other end thereof of the respective short side of said frame.

18. A springy support as set forth in claim 17, wherein said spring bows and said supporting bows are removably connected to said frame and wherein said transverse connecting means and said additional transverse connecting means respectively removably connect said spring bows to each other and each terminal bow to the spring bow adjacent thereto.

19. A springy support as set forth in claim 17, wherein said frame is made from plastics material, and wherein said spring bows, terminal bows, supporting bows, cross connecting means and additional cross connecting means are respectively integrally connected.

Delrin Acetal Resin :Manual, published by Polychernicals Department, E. I. du Pont de Nemours Co., Wilmington 98, Delaware, June 1957, pages 7 and 8 relied upon.

ARTHUR L. LA POINT, Primary Examiner.

6/42. Neely 267102 

1. A SPRINGLY SUPPORT FOR UPHOLSTERY COMPRISING A BASE AND A PLURALITY OF ONE-PIECE SPRING BOWS ARRANGED SIDE BY SIDE AND SECURED TO SAID BASE, SAID SPRING BOWS CONSISTING OF AN ELASTICALLY RESILIENT, NONCORROSIVE SYNTHETIC PLASTICS MATERIAL SELECTED FROM THE GROUP CONSISTING OF ACETAL RESINS, AND HAVING A SUBSTANTIALLY RECTANGULAR CROSS SECTION AND A LONGITUDINALLY EXTENDING REINFORCING RIB ON THE CONCAVE SIDE THEROF. 